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Definability in the local structure of the ω-Turing degrees

Published online by Cambridge University Press:  21 February 2019

Hristo Ganchev
Affiliation:
Faculty of Mathematics and Informatics, Sofia University, Sofia, Bulgaria
Andrey C. Sariev*
Affiliation:
Faculty of Mathematics and Informatics, Sofia University, Sofia, Bulgaria
*
*Corresponding author. Email: [email protected]

Abstract

This article continues the study of the definability in the local substructure $\mathcal{G}_{T,\omega}$ of the ω-Turing degrees, initiated in (Sariev and Ganchev 2014). We show that the class I of the intermediate degrees is definable in $\mathcal{G}_{T,\omega}$.

Type
Paper
Copyright
© Cambridge University Press 2019 

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References

Cooper, S. B. (1972). Distinguishing the Arithmetical Hierarchy. preprint.Google Scholar
Ganchev, H. and Sariev, A. C. (2015). Definability of jump classes in the local theory of the ω-enumeration degrees. Annuaire de Université de Sofia, Faculté de Mathématiques et Informatique 102 115132.Google Scholar
Ganchev, H. and Soskova, M. I. (2012). The high/low hierarchy in the local structure of the ω-enumeration degrees. Annals of Pure and Applied Logic 163 (5) 547566.CrossRefGoogle Scholar
Posner, D. B. and Robinson, R.W. (1981). Degrees joining to 0ʹ. Journal of Symbolic Logic 46 (4) 714722.CrossRefGoogle Scholar
Sariev, A. C. and Ganchev, H. (2014). The ω-Turing degrees. Annals of Pure and Applied Logic 165 (9) 15121532.CrossRefGoogle Scholar
Soare, R. S. (1974). Automorphisms of the lattice of recursively enumerable sets. Bulletin of the American Mathematical Society 80 5358.CrossRefGoogle Scholar
Soskov, I. N. (2007). The ω-enumeration degrees. Journal of Logic and Computation 17 (6) 11931214.CrossRefGoogle Scholar